20523456 has 140 divisors (see below), whose sum is σ = 63066168. Its totient is φ = 6594048.

The previous prime is 20523449. The next prime is 20523463. The reversal of 20523456 is 65432502.

20523456 is a `hidden beast` number, since 205 + 2 + 3 + 456 = 666.

It is an interprime number because it is at equal distance from previous prime (20523449) and next prime (20523463).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 191755 + ... + 191861.

Almost surely, 2^20523456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20523456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31533084).

20523456 is an abundant number, since it is smaller than the sum of its proper divisors (42542712).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20523456 is a wasteful number, since it uses less digits than its factorization.

20523456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The square root of 20523456 is about 4530.2821104209. The cubic root of 20523456 is about 273.7895270377.

Adding to 20523456 its reverse (65432502), we get a palindrome (85955958).

The spelling of 20523456 in words is "twenty million, five hundred twenty-three thousand, four hundred fifty-six".